Helicopters are versatile aircraft in that they are capable of vertical lift and forward propulsion without the need for a runway, unlike most other passenger and cargo transporting style aircraft, such as propeller and jet powered aircraft. Unfortunately, helicopters are limited in forward speed.
In order to have vertical takeoff and landing capability of a helicopter and to have forward flight speed ability of other aircraft, different styles of vertical takeoff and landing (VTOL) aircraft are being introduced. One VTOL aircraft, in particular, is the canard rotor/wing (CRW) aircraft. A canard rotor/wing aircraft provides significant improvements in forward speed over traditional style helicopters. Aircraft of the canard rotor/wing design, in general, include one or more rotor/wings located on an aircraft fuselage that may be operated in a rotary-wing mode and in a fixed-wing mode. The rotor/wings include two symmetrical blades and produce lift irrespective of flow direction.
There is a current desire to increase the drag efficiency of a canard rotor/wing aircraft. Improved drag efficiency results in less fuel needed for a given mission, which in turn reduces the overall vehicle weight. Reduced vehicle weight can reduce vehicle-operating costs and allow for increased payload or cargo carrying capability of the aircraft.
As with traditional helicopters, approximately two-thirds of all drag linked with any canard/rotor wing aircraft can be traced to three features, specifically the rotor, the rotor hub, and the interactions thereof with the fuselage of the aircraft. Thus, there exists a need for an improved canard rotor/wing design with reduced drag associated with the stated features.